Cable winder on tractor

ABSTRACT

A cable winder mounted on a tractor for a construction machine, which uses an electric motor as a prime mover. In the present invention is installed a reel driven with a torque motor. The tension of a hanging cable and the torque of the torque motor is balanced when the machine stands still; when it moves forward, the cable is tensioned and the torque motor reverses, and the cable is unwound from the reel. When the machine moves backward, cable tension decreases, the torque motor normally moves to wind the cable on the reel.

United States Patent Toru Aihara Sagamihara-shi, Japan 71,878

Sept. 14, 19711 Jan. 4, 1972 Caterpillar Mitsubishi Ltd. Tokyo, Japaninventor Appl. No. Filed Patented Assignee CABLE WINDER 0N TRACTOR 2Claims, 6 Drawing Figs.

US. Cl

Int. Cl

Field 01 Search References Cited UNITED STATES PATENTS 5/1907 Shaver191/12.2A H02j 11/02 ..191/12.2 R,

2,450,257 9/1948 Simmons 191/122 R 2,483,760 10/1949 Duncan... 191/122 RUX 3,374,319 3/1968 Stahmer 191/114 Primary Examiner--Arthur L. La PointAssistant Examiner-George H. Libman Art0rneyFryer, Tjensvold, Feix,Phillips & Lempio ABSTRACT: A cable winder mounted on a tractor for aconstruction machine, which uses an electric motor as a prime mover. inthe present invention is installed a reel driven with a torque motor.The tension of a hanging cable and the torque of the torque motor isbalanced when the machine stands still;

when it moves forward, the cable is tensioned and the torque motorreverses, and the cable is unwound from the reel. When the machine movesbackward, cable: tension decreases, the torque motor normally moves towind the cable on the reel.

PATENYED JMI 4 I972 SHEET 2 BF 4 PAIENIEU JAN 4 m2 SHEET 3 UP a CABLEWINDER N TRACTOR The present invention relates to a cable winder mountedon a track-type or wheel-type tractor. Hitherto a tractor with anearthmoving machine using a motor as a prime mover has been employed.Power is supplied from an electric source by means of a cable. Withoutany winder for the cable a tractor connected with a construction orearthmoving machine makes it a rule to advance or retreat dragging thecable, which is in contact with the ground. For this reason there aremany accidents of cable injuries or breakages due to the interference ofobstacles.

In order to avoid such injuries of the cable, it should not be draggedwhen a tractor maneuvers. Assume that a tractor moves forward. The cablemay be extended for a distance equal to the distance covered by thetractor moves backward. The cable may be reduced in length so much. Itis difficult for a cable to stretch or shrink by itself, but it issufficient for a reel to unwind or wind the cable. After all, a cablewinder is to be mounted on a tractor. In the present invention, a torquemotor is used in rotating a winding reel. Normally a cable hangs on theground from the reel mounted above a tractor. The tension of the hangingcable causes a torque on the reel through the cable. The tension of thecable and the torque of a torque motor is equally balanced. When thetractor does not advance or retreat and is in neutral, the torque motoris in equilibrium and the reel will not move. However when a tractorstarts to advance, the tension of torque increases to reverse therotation of the torque motor and to unwind the cable from the reel. Whena tractor starts to retreat, the torque motor rotates normally to wind acable on the reel. As described above, even when a tractor advances orretreats, there is no dragging of the cable. In other words with theadvance or retreat of the tractor the cable wound on the reel makes arelative motion. Further by installing a radial reel assembly and apulley assembly a cable is caused to follow any maneuvering direction ofa tractor.

The primary object of the present invention is to provide a cable winderwith which the operation of the machine is possible while a cablefollows any moving direction of a tractor without being dragged on theground.

Another object of the present invention is to provide a sufficient cablewinder in remote controlling a part of the operating device with anelectric wire from a stationary source of electricity and driving aconstruction machine unattended.

Another object of the present invention is to provide a reel assemblyand a coworking pulley assembly.

An embodiment of the present invention will be described below withreference to the accompanying drawings in order that the presentinvention may be more clearly understood.

FIG. 1 is a side view of a cable winder mounted on a tractor for aconstruction machine.

FIG. 2 is a side view illustrating a hanging cable in FIG. 1.

FIG. 3 is an enlarged view showing the main parts of the cable winderpartially broken away in FIG. ll.

FIG. 4 is a plan view ofa reel assembly in FIG. ll.

FIG. 5 is a side view of a pulley assembly partially broken away in FIG.1.

FIG. 6 is a diagram showing speeds of a torque motor for driving thereel assembly vs. its torque.

In FIG. 1 cable 1 is lifted up to the height 13 of pulley 3 from groundA while it is crawling on the ground from electric source 2 designatedprovisionally and is wound up ontoreel assembly 8 on tractor 60.

On tractor 60 is fixed cable winder assembly 21 and reel assembly 8 aremounted on an inner shaft. The inner shaft is driven with torque motoradjacent to it through a chain mechanism.

In FIG. 1 in light of one cardinal point at point B on pulley 3, thecable hanging from point B to point A is pulled by gravity at point B inthe direction the cable is unwound from the reel. In this case unlessthe reel is braked, the rotation of the reel is prevented with saidtorque motor, or there is some other device, the cable will rotate thereel by the gravity of the cable. In the present invention said torquemotor is adapted to balance cable winding power and gravitationalunwinding power at the stationary state of the tractor. That is, theheight CB of a pulley and distance CA are set so that the force obtainedby multiplying the weight empty of the cable in AB by sprocket ratioequals the cable winding power of the torque motor at the stationarystate of the tractor.

Reel assembly 8 positioned above the cable winder is, as shown in FIGS.3 and 4, composed of block 15 located in the center; a plurality ofstays 11 arranged radially with the center at block 15, the ends ofwhich are fixed to rim 9, these making an under rim; spiral case 13having a bottom mounted in the center of the under rim, part of whichspiral case is welded and integrated with block 15; and a plurality ofstays 12 arranged radially above and outside the spiral. case, the endsof which are fixed to rim 10, making an upper rim. As described above,reel assembly 8 is composed of central block 15, spiral case 13 andupper and under rims, the spiral case being provided inside withconnector 16 and above with detachable cover 114.

The peripheral wall of spiral case 13 is spirally formed to receive andstore cable I wound from outside to inside along the wall, the terminalof which cable is connected to connector 16 mounted on spiral case 13.To the other end of connector 16 is connected a group of lead wires 19.The group of lead wires passes through the trumpet-shaped opening andruns down the inner hole of inner shaft 20.

lnsulated outer pipe 25 is connected to the lower periphery of innershaft 20. Numerous small holes are bored on the pipe. The lead wireseach pass through the holes and soldered on sliprings 26 mountedvertically on an insulator. Brushes 27 each are pressed on eachslipring, and lead wires connected to the other end of the brushes passthrough the holes of case 24 and are led to the outside. Two lead wiresare led to torque motor 17 and all the others to control device 50.

Inner shaft 20 is rotatably supported with two ball bearings 22 and 23.Inner shaft 20 receives the weight of the reel and the cable throughball bearing 22. Between ball bearings 22 and 23, there are distancecollars 29 and 30 and chain sprocket 31 which is connected to anotherchain sprocket 33 via chain 32. Chain sprocket 33 is fixed to shaft 46which is supported with two ball bearings 47 and connected to flexiblecoupling 48. The flexible coupling is connected to the shaft of torquemotor 17. Hence the reel assembly is rotatable through chains 32. Gear52 to rotate together with chain wheel 33 is connected to shaft 46. Itsrotation is transmitted to a stop motion (not shown) via a gear trainand the tractor is stopped just before the cable is unwound from thereel assembly. Chain mechanism 32 is made dustproof by covering it witha case bolted to slipring case 24, the bottom of which is bolted toplate 411. Angle 42 for supporting the torque motor and angle 44 forsupporting torque motor fan 43 are fixed to plate 41 and the tops of theangles are fixed to case 40.

In the cable winder of the present invention, torque motor 17 isvertically positioned to facilitate the driving chain 32. The torquemotor is positively cooled! by the cooling air fed with fan 43 through aduct, and the cooling air which passes through the motor strikes againstplate 49 and diffuses outside the cable winder.

Pulley assembly 3 is supported with fixed bracket 34 via two ballbearings 35. Bar 36 which supports ball bearings 38 and 39 is rotatablysupported with boss 37. Thus pulley assembly 3 is freely rotatable toleft and right. This pulley assembly is, as shown in FIG. 5, composed offour pulleys 4 rotatably mounted on holder 7 through ball bearing 5 andshaft 6. These four gourd-shaped pulleys form a hole as shown in thedrawing at the time of assembling them to pass cable 1 through the hole.The function of the cable winder of the present invention will bedescribed below.

When electricity is started to be supplied from an electric source, theprimary motor, the torque: motor and the motor for driving the fan startto rotate.

1. When a tractor stops:

If the operation is carried out when a tractor stops, the weight emptyof the cable in AB becomes a tension to pull the cable, but the drivingtorque of the torque motor is adapted to balance the tension and thetorque motor will not rotate, which in turn does not make the reel turnto keep the cable still.

2. When a tractor advances:

When a tractor advances, the cable tension pulls the cable from thetractor.

3. When a tractor retreats:

When a tractor moves backward, the cable is loosened, the torque of thetorque motor overcomes the cable tension and the torque motor starts itsregular rotation. As shown in FIG. 6, as the tractor retreats and thetorque of the cable side decreases, the rotational speed N, of thetorque motor increases from zero to u As the reverse speed of thetractor increases further, the rate N of the torque motor increases.Thus the torque motor rotates at the revolution per minute, N,corresponding to the forward speed of the tractor. As described above,when the tractor retreats, the reel makes a regular rotation to wind thecable.

And when the tractor turns left or right, the cable bends in the turningdirection of the tractor by the coworking of the radial reel and therotatable bar to support the pulley assembly; there occurs no unforeseenaccident of the cable being arrested by the shoe when the tractor turnsround.

As described above, the cable winder of the present invention alwaysallows the cable to follow the locus of maneuvering of the tractor(advance, turn, retreat, etc.) without the sliding of the cable alongthe ground, accidents due to cable wear, injuries, and breakages can beeliminated to speed up the operations and secure the safety thereof.

1 claim:

1. A cable winder mounted on a tractor in which motors are used as aprime mover comprising a reel assembly, the center of which is formed bya spiral case holding a connector of a group of lead wires between theouter and inner walls spirally bent and by a block which is fixed to thebottom of the spiral case and which has an opening to pass a group oflead wires through, and which is composed of a pair of upper and underrims prepared by mounting a plurality of stays horizontally and radiallyon the upper and under edges of the center of the reel assemblyrespectively; a shaft rotatably supporting the reel assembly, which isprovided with an inner hole; a vertical torque motor driving the shaftthrough a chain; a plurality of sliprings vertically mounted on thelower part of the shaft; and a pulley assembly supporting the cablewhereby the rotation of the torque motor is controlled only by thetension of the cable hanging on the ground from the reel and thereby thecable is adapted to follow the locus of, or to stop, the maneuver of thetractor.

2. The cable winder according to claim 1 wherein the pulley assembly isfixed to the tip of a bar rotatably fixed to the periphery of the cablewinder and composed of four gourdshaped pulleys to form a cable path inthe center of the pulleys.

i l t 1' t

1. A cable winder mounted on a tractor in which motors are used as aprime mover comprising a reel assembly, the center of which is formed bya spiral case holding a connector of a group of lead wires between theouter and inner walls spirally bent and by a block which is fixed to thebottom of the spiral case and which has an opening to pass a group oflead wires through, and which is composed of a pair of upper and underrims prepared by mounting a plurality of stays horizontally and radiallyon the upper and under edges of the center of the reel assemblyrespectively; a shaft rotatably supporting the reel assembly, which isprovided with an inner hole; a vertical torque motor driving the shaftthrough a chain; a plurality of sliprIngs vertically mounted on thelower part of the shaft; and a pulley assembly supporting the cablewhereby the rotation of the torque motor is controlled only by thetension of the cable hanging on the ground from the reel and thereby thecable is adapted to follow the locus of, or to stop, the maneuver of thetractor.
 2. The cable winder according to claim 1 wherein the pulleyassembly is fixed to the tip of a bar rotatably fixed to the peripheryof the cable winder and composed of four gourd-shaped pulleys to form acable path in the center of the pulleys.